This invention relates generally to manual transmission shifters and, more particularly, to an integrated housing for a ball shifter.
Passenger vehicles equipped with manual transmissions are increasingly supplied with a ball-type cable shifter which mounts the shift lever on a universally movable ball that is mounted in a socket in the shifter housing. This shifter is commonly called a "ball shifter" and is movable about two axes to manipulate cables to shift the transmission. Such a shifter is shown in U.S. Pat. No. 4,693,135--LaRocca, the entire disclosure of which is incorporated herein by reference.
In the LaRocca shifter, one cable is controlled by an extension of the shift lever which extends below the ball. The other cable is controlled by a pin which extends laterally of the ball. The ball is secured in a plastic socket which has a plurality of legs that are expansible to receive the ball. After the ball is in place, the socket is inserted into a mating receptacle in a housing which has a slot to accommodate the shift lever pin. The socket is secured in the housing by a support member which is riveted or bolted to the housing.
A shifter of the LaRocca type is thus composed of a plurality of metal and plastic bits and pieces, all of which require manual assembly. Since each part has a tolerance, tolerance stackup can cause a ball to be tight or loose in its socket. Thus, the same process and design can produce shifters which have a different "feel", since they vary in stiffness or, conversely, in sloppiness. In this situation, tolerance control is extremely important, since these tolerance variations make it difficult to produce a consistently smooth shifter "feel". This adds to manufacture and assembly time and cost.
In this type of shifter, it is desirable to bias the shifter so that, when manually released, it will seek out a centered neutral position. In some shifters, the centering mechanism is located in the vehicle transmission. In some, the transmission will center in one direction only, or not at all. In these cases, a spring must be added to the shifter for centering purposes, adding yet more parts and complexity to the shifter mechanism.
It would be desirable to provide a ball shifter of reduced complexity to simplify and speed assembly.
It would also be desirable to provide a ball shifter which is an integrated assembly that requires fewer parts to reduce assembly time and minimize the effects of tolerance stackup.
It would be further desirable to provide a ball shifter which integrates the spring centering function into the housing structure.